Artificial Gravity

The International Space Settlement Design Competition judges expect
that your team of students will design a Space Settlement that provides
artificial gravity for its occupants. Although there are some schools
of thought advocating zero-gravity habitation in space, the Foundation
Society considers this a strong "quality of life" issue; any proposal for
a space settlement design that does not provide artificial gravity will
need a very compelling argument in order to win favor with the judges.

The judges will, however, favorably consider proposals that advocate
other than one Earth gravity. Proposals should justify their selection
of artificial gravity acceleration; the judges are mostly concerned
that the students have considered implications of their decision (e.g.,
less acceleration enables structural integrity with less weight; more
acceleration could enhance health and fitness of the occupants).

The judges only know of one way to produce artificial gravity with
technology that will be available within the foreseeable future: the
settlement must rotate. If students come up with any other scheme for
providing gravity, they must provide compelling justification. The judges
are also familiar with studies that predict occupants will become ill if
subjected to rotation rates greater than three revolutions per minute;
they will look most kindly on rotation rates of one revolution per minute
or less.

The judges also expect that a settlement which provides artificial
gravity through rotation will have circular cross-sections in those
volumes that are rotating. The figure (from a mid-1970's NASA study)
shows suggested configurations for rotating space settlements. Your
team may choose one of these or a hybrid of several. Non-circular
designs would need very strong justification.

The amount of "gravity" induced by spinning can be calculated,
and it is expected that Space Settlement Design Competition proposals
will specify both rotation rate and the magnitude of artificial
gravity produced. An exercise is included that demonstrates this
calculation.

EXERCISE: Artificial Gravity

How fast does a
Stanford Torus spin to have acceleration equivalent to one Earth
gravity?